Al Qaeda issued another, more urgent public plea Wednesday to the family of American hostage Warren Weinstein to pressure Washington to negotiate for his release, but his wife told ABC News she feels "powerless" to help free him after three years.

The written, English-language message from the core al Qaeda group in Pakistan, where Weinstein, 73, has been suspected of being held against his will for three years as of this week, urged his family to "pressure your government." But there was no new video or photo of Weinstein, whose health is believed to have deteriorated in captivity.

"I was hoping that if they were going to get in touch in some way they would at least show me what he looks like; that would have been a relief to me... this was unsatisfactory," Elaine Weinstein, his wife, told ABC News in an interview on Thursday.

The al Qaeda message addressing the family claimed that, "Your government wants Warren Weinstein to die in prison so that it may absolve itself of responsibility regarding his case. Your government has not made any serious efforts for the release of the prisoner."

But Elaine Weinstein responded that what al Qaeda is asking for "is impossible for us to deliver."

"We are plain, ordinary people, we have no influence with our government – we hope that everyone is doing everything possible to bring Warren home. We are totally powerless. What they are asking for in this message is something that a private family cannot deliver," Weinstein said in the interview Thursday.

One top expert said the new message likely lowers the threat of the former USAID contractor being executed by al Qaeda -- but the demands by the extremist group may go unanswered by the U.S. government.

Al Qaeda repeated past calls for the U.S to free a number of prisoners including Osama Bin Laden's family, admitted 9/11 facilitator Ramzi Binalshibh and the "Blind Sheikh," Omar Abdel Rahman, who was convicted of plotting to destroy New York City landmarks. Weinstein appeared in video pleas last December and in late 2012.

Veteran terrorist hunter Christopher Voss, who is familiar with Weinstein's case, said the good news is that al Qaeda appears anxious for the U.S. to negotiate for Weinstein in the way the government did with the Taliban leadership-in-hiding in its exchange of five top Taliban detainees at Guantanamo for Army Sgt. Bowe Bergdahl in May.

"They are begging for a negotiation. This is another unprompted attempt by al Qaeda to try to get something going on Weinstein," Voss, the FBI's former chief hostage negotiator, told ABC News on Thursday.

Voss also was a key counterterrorism agent in the investigation following the 1993 World Trade Center bombing of the Blind Sheikh, who U.S. officials have told ABC News will die in a U.S. federal prison serving his full life term and will never be freed. Al Qaeda isn't known for releasing hostages, and the U.S. does not as a policy negotiate with those responsible for 9/11.

The good news is that al Qaeda has "lowered the threat level" on Weinstein, Voss said, by telling the world in its statement that "inaction of your government will only lead to your prisoner dying a lonely death in prison."

In other words, Weinstein may be dying already and they are in a hurry to get something in exchange for him, such as their detainees in U.S. custody, or they are willing to let him eventually die of old age as a hostage, Voss said.

"They said if we don't do something he's going to die in captivity. But they're not putting any timeline or conditions on his death," he added.

But the Obama administration has been stung by blowback over releasing five very dangerous killers as a trade for Bergdahl, who is on active duty and under investigation by the Army for his disappearance in 2009 from a combat outpost in eastern Afghanistan. Findings and recommendations for possible charges are expected in September, officials have said.

“I am disappointed that they didn’t get Warren back when they got Bowe Bergdahl back – but they [government] explained it as a totally different situation. I’m brokenhearted," Elaine Weinstein told ABC News.

"Sometimes I think I’m just living in a very long nightmare, and I can’t get up. That’s how it feels – three years or a week – it feels the same, one long nightmare. I just wish someone could shake me out of it," she said. "I get up, he’s not here, he’s in captivity and I have to go on with my day. Every day is the same.”

The administration also is contemplating leaning on European allies to stop paying huge ransoms to al Qaeda offshoot groups -- mostly in North Africa -- who have collected upwards of $90 million or more by taking European captives. That could further frustrate efforts to free Weinstein and a handful of other American hostages held in places like Syria and Iran, such as former FBI Agent Robert Levinson.

For its part, the State Department said this week that officials are "monitoring" Weinstein's plight.

"We remain concerned for the safety and well-being of Mr. Weinstein, and we continue to monitor the situation closely, as well as to work actively with Pakistani authorities to try to secure his release. We remain in regular contact with Warren Weinstein’s family in the United States and are providing all possible consular assistance. The United States strongly condemns kidnappings of any kind, and we call for the immediate release of the victim and the prosecution of those responsible," a State Department official said on Wednesday.